CN112065924A

CN112065924A - Belt pulley decoupler with axis of rotation

Info

Publication number: CN112065924A
Application number: CN202010528945.6A
Authority: CN
Inventors: M·黑斯勒; A·斯塔弗尔; L·索瑞特; A·鲁施; M·凯斯勒
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2019-06-11
Filing date: 2020-06-11
Publication date: 2020-12-11
Anticipated expiration: 2040-06-11
Also published as: CN112065924B; DE102019115747A1

Abstract

The invention relates to a pulley decoupler (1) having a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), the pulley decoupler (1) comprising a torsional vibration damper (5) which comprises at least: an input side (6); an output side (7); at least one intermediate element (8, 9, 10) between the input side and the output side; two rolling bodies (11, 12) per intermediate element, the intermediate element having two drive tracks (13, 14), the input side and the output side each having a complementary counter track (15, 16), the rolling bodies being rollably guided between the respective drive track and the complementary counter track; and at least one energy storage element (17, 18, 19) by means of which the intermediate element is supported in a manner that can be vibrated. The energy storage element is arranged to have a vector component (20) acting on the intermediate element in a circumferential direction (22) and/or to provide only rolling bodies as rollable bodies for the respective intermediate element.

Description

Belt pulley decoupler with axis of rotation

Technical Field

The invention relates to a belt pulley decoupler having an axis of rotation for a belt drive of an internal combustion engine, a belt drive for a drive train having such a belt pulley decoupler, a drive train having such a belt drive, and a motor vehicle having such a drive train.

The invention relates to a pulley decoupler with a rotational axis for a belt drive of an internal combustion engine, wherein the pulley decoupler comprises a torsional vibration damper having at least:

-an input side;

-an output side;

-at least one intermediate element between the input side and the output side;

two rolling bodies per intermediate element, wherein the at least one intermediate element has two drive tracks, wherein the input side and the output side each have a complementary counter track, wherein the rolling bodies are rollably guided between the respective drive track and the complementary counter track; and

at least one energy storage element, by means of which the at least one intermediate element is supported in a manner that can be vibrated.

The main feature of the belt pulley decoupler is that the energy storage elements are arranged with a vector component in the circumferential direction acting on the respective intermediate element and/or that only rolling bodies are provided as rollable bodies for each intermediate element.

Background

In belt drives using excitation with periodic disturbances (for example in auxiliary drives of internal combustion engines), the pulley decoupler acts as a torsional compliance (toronto snachgiebigkeit) introduced for the pulley of the driven device. The aim here is to shift the resonance occurring in a speed range as far as possible below the operating speed. In order to be able to achieve largely supercritical operation (with good vibration isolation of the output part from disturbances) in the drive part of the belt drive, it is desirable to achieve as high a torsional compliance as possible, i.e. a low torsional stiffness. However, the pulley decoupler must at the same time satisfy the maximum drive torque, which requires a correspondingly large torsion angle with low torque stiffness. However, in a given installation space, the angle of torsion that can be assumed is naturally limited by the capacity of the energy store used and the sufficiently firmly configured components that are located in the torque flow.

Various types of torsional vibration dampers are known from the prior art. A torsional vibration damper is known, for example, from EP 2508771 a1, in which the output side is provided with a (double) cam which acts on a rod-shaped intermediate element, wherein the intermediate element is connected to the input-side disk in a tiltable manner. The intermediate element is prestressed against the output-side cam by means of a compression spring and is biased against the compression spring when passing the cam geometry. The compression spring is connected in a pressure-transmitting manner to the input side opposite the intermediate element, so that a torque is introduced from the input side to the output side via the compression spring.

A further variant of a torsional vibration damper is known from FR 3057321 a1, in which a rod-shaped spring body in the form of a (free-form) solid spring is arranged on the output side, wherein the spring body has a ramp-like drive track on the radial outside, which is connected in a torque-transmitting manner to a roller rolling on the drive track. The roller is rotatably supported on the pin. If torsional vibrations occur, a relative movement is caused between the spring body and the respective roller, and the spring body is offset in a rod-like manner from the roller against its spring force in its rotational relative movement relative to the roller due to the ramp-like drive track. Thereby damping the torsional vibration.

Both the rod of EP 2508771 a1 and the spring body of FR 3057323 a1 are technically difficult to handle and/or expensive to manufacture or assemble if low dissipation, i.e. high efficiency, is desired.

For example, WO 2018/215018 a1 discloses a torsional vibration damper, in which two intermediate elements are provided, which are supported on the output side and on the input side by rolling elements. The rolling bodies run on complementary drive tracks, so that the intermediate element is positively guided. The two intermediate elements are prestressed relative to one another by means of the energy storage element, so that the functionally effective stiffness of the energy storage element can be designed independently of the torque transmission. For many applications, it is required on the one hand to reduce the natural frequency of the torque transmission system and at the same time to be able to transmit high torques. From the first requirement, the functionally effective stiffness must be low. From the second requirement, the energy storage element must have a high rigidity. These conflicting requirements can be solved by means of the rolling elements and the drive track. Torque is transmitted between the input side and the output side only by means of the gear tracks and the rolling bodies arranged between them. The stiffness, which is functionally effective, i.e. changes the natural frequency, translates into a small spring travel due to the small gradient and large torsion angle. The cam mechanism results in a (arbitrarily) low functionally effective stiffness. It is therefore advantageous in this system to be able to design the energy storage element independently of the (maximum) transferable torque. However, the illustrated embodiment with a large number of individual rolling bodies and high requirements on the complementary drive track is complicated and expensive to produce and assemble. Therefore, the system is not competitive in all fields.

Disclosure of Invention

Starting from this, the invention is based on the object of at least partially overcoming the disadvantages known from the prior art. The features according to the invention emerge from the independent claims, advantageous configurations of which are set forth in the dependent claims. The features of the claims can be combined in any technically meaningful manner, wherein for this purpose also the features from the explanations given below and from the drawings can be considered, which comprise additional embodiments of the invention.

In the following, reference is made to the axis of rotation if no other explicit description of the axial, radial or circumferential direction and the corresponding concept is given. Ordinal numbers used in this description are for clarity of distinction only and do not reflect the order or hierarchy of the parts noted unless otherwise expressly specified. An ordinal number greater than one does not necessarily mean that there must be another such element mandatory.

The invention relates to a belt pulley decoupler having a rotational axis of a belt drive for an internal combustion engine, wherein the belt pulley decoupler comprises a torsional vibration damper having at least the following components:

-an input side for receiving a torque;

-an output side for outputting a torque;

at least one intermediate element in the torque-transmitting connection between the input side and the output side;

a first rolling body and a second rolling body of each intermediate element, wherein the at least one intermediate element has a first drive track for the rolling of the first rolling body and a second drive track for the rolling of the second rolling body, wherein the input side has a first counter track complementary to the first drive track and the output side has a second counter track complementary to the second drive track, wherein the first rolling body can be guided rollably between the first drive track and the first counter track and the second rolling body can be guided rollably between the second drive track and the second counter track; and

at least one energy storage element, by means of which an intermediate element corresponding to the energy storage element is supported in a vibratable manner.

The main feature of the belt pulley decoupler is that the energy storage element is arranged to have a vector component in the circumferential direction that acts on the corresponding intermediate element.

A belt pulley decoupler is proposed which is suitable for use in a belt drive having at least two belt pulleys, namely at least one drive pulley and at least one driven pulley, which are connected to one another by means of a belt in a torque-transmitting manner. Such a belt drive is used, for example, in internal combustion engines, in which a drive disk is connected indirectly or directly to a burner shaft (verbrennerwell) as a torque source, for example, in the main operating state of the internal combustion engine. The driven disk is connected, for example, to the rotor shaft of an auxiliary device (for example, an air conditioning compressor or a motor generator). The belt pulley decoupler can be used both in the driving pulley and in the driven pulley. For many applications, the pulley decoupler does not allow deviations in its mounting dimensions from the conventional mounting dimensions of the corresponding pulley, but for most applications the use of a suitable vibration decoupling or advantageous change of the resonant frequency is at least not allowed to be greater than for conventional pulley decouplers.

It is now proposed to use a torsional vibration damper configured as follows. The torsional vibration damper proposed here has a small number of individual components and only a small number of rolling bodies and complementary drive tracks, which are referred to as drive tracks on the intermediate element side and (complementary) counter-tracks on the input side and output side. The input side is provided here for receiving torque, wherein it is not excluded here that the input side is also provided for outputting torque. For example, the input side forms a torque input in the main state (for example in the case of a so-called drag torque from a drive shaft, i.e. a torque output of the internal combustion engine and/or the electric machine). The output side is accordingly provided for outputting a torque, wherein the output side is preferably also provided for receiving a torque (for example from a motor generator) for starting the internal combustion engine. The output side thus forms the input side of the so-called push torque, for example, when the belt drive of the drive train is used in the auxiliary state, i.e., in the exemplary embodiment described above, at least one auxiliary device outputs the input torque to the internal combustion engine.

In order to prevent torsional vibrations from being transmitted directly from the input side to the output side or vice versa, at least one intermediate element, preferably at least two intermediate elements, is provided. At least one intermediate element is arranged in the torque transmission connection between the input side and the output side. The at least one intermediate element can be moved relative to the input side and relative to the output side in such a way that torsional vibration energy is introduced into the intermediate element and thus onto the energy storage element with a predetermined (functionally effective) stiffness. Thus, the natural frequency of the system incorporating the torsional vibration damper, its mass and stiffness functions can be varied, preferably reduced.

The intermediate element is supported on itself or on an adjacent intermediate element by means of at least one energy storage element (for example an arc spring, a leaf spring, a gas pressure accumulator or the like). The energy storage element is supported in a force-or torque-transmitting manner on a corresponding connecting device, preferably in one piece, of the respective intermediate element. For example, the connecting means are contact surfaces and/or rivet points.

At least one intermediate element is supported on the input side and on the output side by means of rolling bodies connected in series, wherein the intermediate element has a drive track for each of the rolling bodies and complementary counter tracks are formed on the input side and on the output side for the same (counter) rolling body. The complementary counter track is formed by the output side or by the input side, preferably in one piece with the input side and the output side, respectively. Torque is transmitted through the corresponding track and the drive track. Torque is not transmitted between the input side and the output side via the at least one energy storage element.

For example, if a torque is introduced, for example from the input side, the rolling bodies roll on the transmission track and the complementary counter track from the rest position in the respective direction (upwards) on the ramp-like transmission track due to the torque gradient that exists as a result of the torsional vibration damper. The upward scrolling is referred to herein as work for illustration only. Rather, the reaction force of the energy storage element is overcome due to the geometrical relationship. Rolling down therefore means that the energy stored by the energy storage element is output in the form of a force acting on the corresponding intermediate element. Therefore, upward and downward do not necessarily correspond to spatial directions, even in a coordinate system that rotates with it.

By means of this torque-dependent movement, the rolling bodies force the respective intermediate element into a relative movement with respect to the input side and the output side, and the counteracting energy storage element is correspondingly tensioned. For example, in the case of torsional vibrations, if the applied torque changes and at the same time a rotational speed difference occurs between the input side and the output side, the inertia of the other (torque-absorbing) side, here the inertia of the output side, opposes the applied torque, and the rolling elements roll back and forth (in a predetermined manner) on the drive track and on the complementary counter track about the position corresponding to the applied torque. The rolling bodies therefore work against the energy storage element tensioned according to the torque magnitude, so that the natural frequency changes compared to the rest position or the torque transmission without a torsional vibration damper (but with the same flywheel mass).

This force is received by a correspondingly embodied energy storage element in the form of compression, tension, torsion or other energy storage, and is transmitted to the respective other side, here for example the output side, with a time delay, preferably (almost) without dissipation. Thus, the torque input quantity (here, for example, on the input side) comprising the torsional vibrations is preferably transmitted (almost) loss-free, time-variable to here, for example, the output side. Furthermore, as described above, the natural frequency is not constant, but depends on the torque gradient and thus on the applied torque due to the changeable position of the intermediate element.

In the opposite case, in which a torque input is introduced via the output side for output to the input side, the rolling elements are correspondingly caused to roll on the drive track (upwards) in the other direction (opposite to the previously described introduction of torque via the input side). This movement of the rolling bodies causes the energy storage elements to be loaded in the other direction, or, in the case of a pair arrangement, to be unloaded at, for example, the first energy storage element loaded according to the above-described exemplary embodiments and loaded at the respective other, for example, the second energy storage element. When two or more intermediate elements are supported on opposite sides by respective (common) energy storage elements in a circular arrangement, all energy storage elements are tensioned, for example in the manner of a screw clamp, by a radial inward movement of the energy storage elements.

When the torque changes, as occurs in torsional vibrations, the at least one energy storage element is displaced about a position corresponding to the applied torque, and the stored energy is transmitted in the form of a changing, i.e. time-delayed, movement in co-action with the rolling bodies rolling between the respective drive track and the complementary counter-track, here to the output side. This changes the natural frequency of the torque transmission system with the torsional vibration damper engaged.

In one embodiment, two or more intermediate elements are provided, which are preferably arranged rotationally symmetrically with respect to the axis of rotation, so that the torsional vibration damper is balanced by simple means. For a small number of components and (transmission) rails, an embodiment with exactly two intermediate elements is advantageous.

Preferably, two energy storage elements are provided in each case for acting on the (single) intermediate element, wherein the energy storage elements are arranged opposite one another and preferably enter into a state of equilibrium with one another in each case with the embodiment of the drive track and the complementary counter-track. In an alternative embodiment, at least one positive guide is provided, by means of which at least one of the intermediate elements is guided geometrically, for example, forced in the manner of a rail or a groove and a pin or an embedded spring which is gripped.

According to this proposal (deviating from the embodiments proposed below), the energy storage element acts on the respective intermediate element in a force direction having a vector component in the circumferential direction. The circumferential direction is defined on a circle concentric with respect to the axis of rotation. In one embodiment, the circumferential direction is constantly oriented, translationally oriented on a constant circle or constantly or translationally oriented on a variable circle by the movement of the corresponding intermediate element. The circle is at least so large that it contacts the intermediate element, preferably so large that it intersects a contact point or is tangent to a contact surface at the location of which a force is transmitted between the associated energy storage element and the corresponding intermediate element. The circumferential direction is oriented perpendicular to a radius centered on the axis of rotation. The respective base radii intersect the contact points or contact surfaces of the energy storage element and the intermediate element. Thus, a force direction is generated on the intermediate element with a large vector component in the circumferential direction, preferably a force direction with a vector component in the circumferential direction which is larger than the vector component in the radial direction. That is, the forces acting on the intermediate element are not purely radially oriented, but only tangential to the circumferential direction (at the contact point) or have a radial vector component and a tangential vector component (at the contact point). Thus, a force direction is obtained which can be conducted into the same intermediate element (from the other side), for example, by means of a helical arc spring, or into an adjacent intermediate element substantially in the circumferential direction. This can, for example, replace a deflection (or oscillation) of the energy storage element only in the (radial) transverse direction, in addition to or only in the circumferential direction.

In an advantageous embodiment, the intermediate element is supported in an insufficiently defined manner, for example only in a radially defined manner, by the rolling elements, wherein the at least one energy storage element defines a movement occurring as a result of the force introduction direction, for example only in the circumferential direction. Alternatively, additional guides are provided for the intermediate element.

The torsional vibration damper proposed here can be implemented in a small installation space due to its relatively small number of components and can also be produced at low cost. Furthermore, the torsional vibration damper can be used for large torques to be transmitted while the vibration stiffness is very low, since the ramp-like transmission track (and the complementary counter track) produces a rolling transmission of approximately arbitrary reduction ratio. The deceleration ratio has an influence on the required spring travel, so that the stiffness of the rigid energy storage element is reduced, i.e. softer, due to the extended effective spring travel by means of the rolling gear.

According to a further aspect, a belt pulley decoupler is proposed, having an axis of rotation for a belt drive of an internal combustion engine, wherein the belt pulley decoupler comprises a torsional vibration damper having at least the following components:

-an input side for receiving a torque;

-an output side for outputting a torque;

at least two intermediate elements in the torque-transmitting connection between the input side and the output side;

-a first rolling element, a second rolling element of each intermediate element,

wherein the intermediate elements each have a first transmission path for the rolling movement of the first rolling elements and a second transmission path for the rolling movement of the second rolling elements,

wherein the input side has a first counter track complementary to the first drive track and the output side has a second counter track complementary to the second drive track, wherein the first rolling bodies are rollably guided between the first drive track and the first counter track and the second rolling bodies are rollably guided between the second drive track and the second counter track; and

a number of energy storage elements corresponding to the number of intermediate elements, by means of which the respective intermediate elements corresponding to the energy storage elements are supported in a vibratable manner,

wherein each of the intermediate elements is supported on the respective at least one adjacent intermediate element by means of the respective energy storage element.

The main feature of the belt pulley decoupler is that only a first rolling element and a second rolling element are provided as rollable bodies for each intermediate element.

The belt pulley decoupler here proposes a function in accordance with the above description and in this respect reference is made to the above description. In addition, with regard to the torsional vibration damper, reference is made to the preceding explanations of the basic principle, as well as to the definition and interrelationships between the input side, the output side, the respective intermediate element and the corresponding energy storage element, and the rolling bodies and the corresponding drive track and the corresponding track. In contrast to the above description, at least two intermediate elements and at least one, preferably two energy storage elements must be provided, wherein the intermediate elements are supported relative to one another in a force-transmitting manner by means of at least one energy storage element.

According to this proposal (deviating from the embodiment of the aforementioned proposal), at least one energy storage element must be supported by the rolling bodies in an insufficiently defined manner, for example in a manner defined only in the radial direction, in such a way that only two rolling bodies, namely a single (e.g. first) rolling body for the input side and a single (e.g. second) rolling body for the output side, are provided in the respective intermediate element. The at least one energy storage element, which acts on the intermediate element and is supported on at least one (directly) adjacent intermediate element, for example defines the movement due to the force introduction direction only in the circumferential direction. For a reliable configuration, for example, a positive guide is additionally provided, by means of which the movement of the respective intermediate element is (geometrically) over-defined.

It is further proposed that the torsional vibration damper has the features of the above-described embodiments.

In this embodiment, therefore, the respective intermediate element of the plurality of intermediate elements is supported by only two rolling elements, i.e. is supported in an undefined manner or is only supported with certainty, as long as the forces for fixing the position of the drive track relative to the complementary counter-tracks and the rolling elements rolling between them and the degrees of freedom deliberately achieved on the drive track, for example, are implemented as insignificant equilibrium positions, are not taken into account. This force is supported, for example, during operation by an inertial reaction to the centrifugal force (centrifugal force). The degrees of freedom of the drive rail, which are deliberately implemented, for example, as an insignificant balance, are received in a defined manner by the two energy storage elements. For example, rolling elements rolling on the drive tracks (and complementary counter-tracks) cause a motion with radial and/or tangential vector components. Thereby, a path is traveled which is stored as potential energy in at least one of the respective energy storage elements. Furthermore, the energy storage element preferably also exerts the required force, for example a force acting only radially, so that the counter track and the transmission track are held relative to one another in such a way that the counter rolling elements can move between them only in a rolling manner. The movement of the rolling bodies therefore always causes a relative movement between the counter track and the complementary transmission track and thus between the intermediate element and the input side and the output side. Support in the radial direction and/or forced guidance of the intermediate element, for example by means of a large number of rolling elements, is not necessary.

In addition, in an advantageous embodiment of the belt pulley decoupler: exactly three intermediate elements and exactly three energy storage elements are provided, wherein the first intermediate element and the second intermediate element are supported by the first energy storage element, the second intermediate element and the third intermediate element by the second energy storage element, and the first intermediate element and the third intermediate element are supported by the third energy storage element.

In this embodiment, on the one hand, the number of intermediate elements, drive tracks, counter tracks, rolling bodies and energy storage elements is still small, while on the other hand, the expenditure in terms of manufacturing tolerances of the drive tracks and counter tracks is reduced compared to a forced guidance with more than two rolling bodies per intermediate element. In this embodiment, deviations from the ideal orientation of the intermediate element in the rest position, which are predetermined by geometric conditions, for example, as a result of manufacturing, are tolerable to a greater extent and/or can be compensated for by the energy storage element during the calibration process, within the scope of the design.

In addition, in an advantageous embodiment of the belt pulley decoupler: the at least one intermediate element is supported solely by the at least one corresponding energy storage element and by the rolling bodies.

In this embodiment, the intermediate element is brought into stable equilibrium without additional (positive) guide elements only by virtue of the interaction of the transmission track, the complementary counter track and the respective rolling bodies with the corresponding energy storage element. A stable equilibrium here means that the intermediate element cannot be drawn at least from the nominal position in accordance with the designed torque amplitude and torque oscillation. At least for mobile applications, the balance is stable, so that (according to design) transverse forces, such as chatter, also cannot bring this arrangement out of the nominal position, e.g. the rolling bodies cannot be removed from one of their tracks. The vector component of the force of the energy storage element in the radial direction or perpendicular to the drive track and the (applied section of the) corresponding track is always greater than the (external) force to be removed.

This ensures that the force direction of the introduced force of the energy storage element (i.e. the orientation of the force vector along or parallel to the line of action), which extends through the rolling center (rolling axis) of the rolling element and is oriented perpendicularly to the drive track and the complementary counter-track, intersects the line of action of the resulting (counter) force caused by the rolling element independently of the offset of the intermediate element at the moment equilibrium point of the intermediate element. Thus, there is a moment balance on the intermediate element around the moment balance point of the intermediate element. In essence, this force contribution corresponds to the force vector of the force introduced via the rolling elements or the force contribution of the energy storage element acting on the intermediate element. That is, if the force of the energy storage element increases, the resultant force caused by the rolling elements also increases in the structural rule. The force vectors in the two opposing energy storage elements thus form a (closed) force polygon, i.e. the force sum is zero according to the vector addition principle.

In addition, in an advantageous embodiment of the torsional vibration damper, it is provided that: the two rolling bodies are arranged radially spaced apart from one another.

The advantage of this embodiment is that a small installation space is required in the circumferential direction, so that, for example, the intermediate element can be implemented narrowly in the circumferential direction and thus more installation space can be provided for the energy storage elements, and thus, for example, a large torsion angle and thus a small functional stiffness can be provided at the same time as a high stiffness of the at least one energy storage element.

In addition, in an advantageous embodiment of the torsional vibration damper, it is provided that: the two rolling bodies are arranged spaced apart from one another in the circumferential direction.

An advantage of this embodiment is that a small radial space is required, so that for example the intermediate element can be arranged on a large circumferential circle and thus, for example, a large torsion angle and thus a small functional stiffness can be provided at the same time as a large stiffness of the at least one energy storage element. Alternatively or additionally, torque can be transmitted through the same transmission track and thus with equal magnitude.

In an advantageous embodiment of the torsional vibration damper, it is furthermore proposed that the two rolling bodies are arranged radially and spaced apart from one another in the circumferential direction.

In this embodiment, the advantages of the embodiments described above can be combined with one another or can be approximated to the ideal case with small deviations in each case.

In addition, in an advantageous embodiment of the belt pulley decoupler: the drive track and the respectively complementary counter track each comprise a traction torque pair having a first drive curve and a propulsion torque pair having a second drive curve, wherein the traction torque pair is provided for transmitting a torque from the input side to the output side, wherein the propulsion torque pair is provided for transmitting a torque from the output side to the input side, wherein the first drive curve and the second drive curve have at least locally mutually different drive profiles.

Basically, the tractive torque and the propulsive torque do not differ in the theoretical application. Thus, these terms should be considered neutral and are only used to simply distinguish the noted torque transmitting direction. These terms are taken from the generic name in the drive train of a motor vehicle, but can be transferred to other applications accordingly. In the case of a traction torque transmission, for example, a traction torque pair is applied from the input side to the output side, wherein the rolling bodies on the traction torque pair roll (upward) against the opposing force of the energy storage element with increasing torque. Thus, the potential energy of the antagonistic energy storage element increases, for example is tensioned and thereby changes the stiffness. Thus, the torsional vibration resists the greater force of the opposing energy storage element with increasing torque, and the natural frequency changes accordingly. This applies correspondingly to the thrust torque pair, wherein the rolling bodies are forced to roll (upward) on the thrust torque pair as a result of the loading of the energy storage element.

In this embodiment, the first and second transmission curves, which each start from a common point in the rest position, are provided with different transmission profiles. The stiffness characteristic of the torsional vibration damper can therefore be set (differently) for the drag torque and the push torque in a personalized manner.

In one embodiment, for example, a low stiffness is required for transmitting the drag torque, which can be achieved by a correspondingly larger torsion angle (smaller reduction ratio, i.e. smaller denominator of the transmission ratio) than is desired for the pushing torque (larger reduction ratio). Furthermore, for example, an increasing or decreasing stiffness profile, or even a multiple-change stiffness profile, is desired. For example, a small stiffness increase is provided in the region close to idle, a steep stiffness increase is provided for the main load torque, which is in turn reduced in a gradually decreasing manner, and an increasing stiffness increase is provided again until a maximum transmission value of the transmittable torque is reached.

The transmission path and the complementary counter path are designed in such a way that they correspond to the respective offset position of the intermediate element, so that the transmission curve is superimposed on the movement of the intermediate element. The drive rail and the complementary counter rail are preferably embodied in the manner described above for torque compensation, preferably so that the intermediate element does not require additional (positive) guiding means.

In an advantageous embodiment of the torsional vibration damper, furthermore, provision is made for: at least one intermediate element is prestressed by means of two resistant energy storage elements.

In this embodiment, the pretensioning of the energy storage element against the rolling bodies by the intermediate element or the intermediate elements is reliably set in a well-controlled manner. For example, in the case of identical energy storage element configurations, the dependence on component tolerances, for example the spring characteristic of the energy storage elements, is small in that the tolerances decrease with respect to one another, for example, the stiffness deviating downwards from the nominal stiffness of the first energy storage element is compensated or reduced by the stiffness deviating upwards of the second energy storage element. In the case of the same deflection direction, the pretension is reduced or increased overall compared to the setpoint pretension, but due to the counteracting effect, for example, compensation is still carried out on both sides of the intermediate element. In one embodiment, only the rest position of the intermediate element is changed. The tolerance is preferably so small that the rest position remains within a predetermined tolerance range. In the embodiment with three intermediate elements, the (three) energy storage elements are connected to one another in such a way that the first (or second) energy storage element of the first intermediate element is also in antagonistic connection with the second (or first) energy storage element of the second intermediate element and a compensating effect is achieved for component tolerances of the energy storage elements. Overall, therefore, the required manufacturing accuracy, assembly or calibration outlay and/or the costs of the standard component are reduced due to the lower component quality.

In an advantageous embodiment of the torsional vibration damper, furthermore, provision is made for: the at least one intermediate element is pretensioned by means of two opposing energy storage elements, wherein preferably a first energy storage element exerts a first force and a first force direction on the respective intermediate element and a second energy storage element exerts a second force and a second force direction on the respective intermediate element, wherein the first force and the second force differ from each other in the rest position and/or the first force direction and the second force direction differ from each other in the rest position.

A helical compression spring with a straight spring axis, also called a (pure) cylindrical helical compression spring, is a widely used standard component, the elasticity and (low) dissipation characteristics of which are well utilized and can be simply controlled. Simple means can be used to compensate for tolerances in the length of the structure or tolerances in the spring characteristic over a predetermined installation length. Furthermore, such helical compression springs do not require additional guidance, which would otherwise cause friction and thus may have reduced efficiency and/or make it more difficult to obtain damping characteristics due to hysteresis effects. Furthermore, helical compression springs enable a large variation of the spring characteristic curve, which can be set in particular by the helical pitch, the wire thickness, the ratio of the installation length to the relaxation length and the material selection.

Furthermore, the helical compression spring with a straight spring axis is fracture-proof in comparison to springs of other types of construction, for example steel springs, and in some embodiments can be loaded and compacted, so that in the event of an overload on the torsional vibration damper, depending on the design, in such an embodiment in which the energy storage element can be compacted, no additional securing element has to be provided to prevent the energy storage element from fracturing. Furthermore, the helical compression spring has the following advantages: the high spring stiffness and the long spring travel enable a large torque to be introduced via the at least one energy storage element on the one hand, and on the other hand, a suitable movement reduction ratio can be set by means of the transmission track, so that a reduced movement amplitude of the intermediate element is achieved in relation to the amplitude of the torsional vibrations, and thus torsional vibrations are induced in the very small spring travel of the helical compression spring. As a result, the helical compression spring resists torsional vibrations with a (moderate) small force despite having a high stiffness.

In addition, in an advantageous embodiment of the belt pulley decoupler: the at least one energy storage element is a helical compression spring having a straight spring axis.

Furthermore, the helical compression spring with a straight spring axis is fracture-proof in comparison to springs of other types of construction, for example steel springs, and in some embodiments can be loaded and compacted, so that in the event of an overload on the torsional vibration damper, depending on the design, in such an embodiment in which the energy storage element can be compacted, no additional securing element has to be provided to prevent the energy storage element from fracturing. Furthermore, the helical compression spring has the following advantages: the high spring stiffness and the long spring travel enable a large torque to be transmitted via the at least one energy storage element on the one hand, and on the other hand, a suitable movement reduction ratio can be set by means of the transmission path, so that a reduced movement amplitude of the intermediate element is achieved in relation to the amplitude of the torsional vibrations, and thus torsional vibrations are induced in the very small spring travel of the helical compression spring. As a result, the helical compression spring resists torsional vibrations with a (moderate) small force despite having a high stiffness.

According to another aspect, a belt drive for a drive train is proposed, which has at least the following components:

-a first belt pulley for connection with a drive shaft of a drive machine;

-a second belt pulley for connection with a rotor shaft of an auxiliary device; and

a belt connecting the first belt pulley and the second belt pulley in a torque-transmitting manner,

wherein the first pulley and/or the second pulley comprise a pulley decoupler according to any one of the preceding claims.

The belt drive is provided for transmitting torque from the drive machine to the auxiliary device and vice versa, for example in the case of a motor generator as an auxiliary device. For this purpose, belt discs are provided on at least two connected shafts, namely on at least one drive shaft of at least one drive machine (for example an internal combustion engine) and on at least one rotor shaft of at least one auxiliary device (for example an air conditioning compressor), in each case in a torque-proof connection. A belt is tensioned on the belt pulley such that a torque can be transmitted to the other belt pulley in a friction-locking or form-locking manner into a traction force (traction means, for example a V-belt) or a pushing force (pushing the chain belt). At least one of the belt pulleys, preferably the belt pulley on the drive shaft embodied as a crankshaft, comprises a belt pulley decoupler with a torsional vibration damper according to an embodiment of the preceding description. The torsional vibrations are thus decoupled from the rest of the belt drive, for example the rotor shaft of the auxiliary device, by appropriately shifting the natural frequency range of the belt drive. At the same time, the belt pulley decoupler can be implemented with small installation dimensions, so that it can be integrated into a conventional belt pulley despite meeting the usual transmission ratio requirements (i.e. the diameter ratio of the belt pulley).

According to another aspect, a drive train is proposed, which has at least the following components:

-a drive machine having a drive shaft;

-an auxiliary device having a rotor shaft; and

a belt drive according to the above-described embodiment, by means of which the drive machine and the auxiliary device are connected to one another in a torque-transmitting manner.

The drive train is provided for transmitting a torque, which is provided by a drive machine, for example an internal combustion engine or an electric drive machine, and which is output via its output shaft, to at least one consumer. In motor vehicle applications, an exemplary consumer is at least one drive wheel for propelling a motor vehicle, for example a motorcycle, and additionally an auxiliary device, for example a generator for providing electrical energy. In one embodiment, a plurality of drive machines, for example an internal combustion engine and at least one electric machine, for example a motor generator, are provided in a hybrid drive train. Such motor generators form, for example, auxiliary devices and are used both for receiving torque (for generating electrical energy) and for outputting torque (for starting the internal combustion engine). The belt drive enables a torque transmission between the auxiliary device and the drive machine, wherein the natural frequency is suitably shifted in at least one of the belt pulleys by means of the belt pulley decoupler, so that the torque-receiving device, for example the auxiliary device, is protected from resonant oscillations, i.e. vibration decoupling. The belt drive proposed herein has a small installation size and can replace conventional belt drives without other required changes. Furthermore, efficiency is improved relative to systems having other decoupling devices.

According to a further aspect, a motor vehicle is provided, which has at least one drive wheel which can be driven by means of a drive train according to one embodiment of the above description.

Nowadays, most motor vehicles have front-wheel drive and the drive machines, for example internal combustion engines and/or electric drive machines, are arranged partially in front of the driver's cabin and transversely to the main driving direction. The radial installation space is just particularly small in this arrangement, and therefore the use of a drive train with components of small installation dimensions is particularly advantageous. The drive train in a motor-driven two-wheeled vehicle is similarly configured, which requires an increased output over known two-wheeled vehicles at all times while maintaining an equal installation space. With the hybridization of the drive train, this problem is also exacerbated for rear axle arrangements and here also in the longitudinal arrangement as well as in the transverse arrangement of the drive assembly.

In the motor vehicle proposed here with the drive train described above, a high efficiency is achieved due to a high running stability and thus a very constant belt tensioning by integrating a very efficient torsional vibration damper in at least one of the belt pulleys of the belt drive of the drive train. At the same time, the required installation space is at least not larger than that conventionally used, and the costs are not increased compared to conventional vibration decoupling systems.

Passenger cars correspond to vehicle classes according to, for example, size, price, weight and power, wherein this definition is subject to constant changes according to market demand. In the us market, the vehicle classes of small vehicles and miniature vehicles correspond to the super-small vehicle classes according to the classification in europe, and in the uk market such vehicles of small vehicle and miniature vehicle classes correspond to the super-mini class or the city vehicle class. An example of a mini car class is the popular up! Or Reynolds Twingo. Examples of minicar classes are alpha RomeO MiTo, Volkswagen Polo, Ford Ka +, or Reynolds Clio. The known full hybrid vehicles in the small vehicle class are BMW i3 or yota Yaris hybrid.

Drawings

The above invention is explained in detail in the related art background with reference to the drawings showing preferred configurations. The invention is not limited to the purely schematic representations, in which it should be noted that the figures are not to scale in nature, nor are they suitable for defining dimensional relationships. It shows

FIG. 1: a schematic diagram of a first embodiment of a torsional vibration damper;

FIG. 2: a schematic diagram of a second embodiment of a torsional vibration damper;

FIG. 3: a schematic representation of the forces exerted on the intermediate element;

FIG. 4: force polygon according to the force applied in fig. 3;

FIG. 5: a torque-torsion angle diagram having a first transmission curve;

FIG. 6: a torque-twist angle map having a second drive curve;

FIG. 7: a torque-twist angle diagram having a third drive curve;

FIG. 8: a torque-twist angle diagram having a fourth and a fifth transmission curve;

FIG. 9: a schematic cross-sectional view of a pulley decoupler with a torsional vibration damper; and

FIG. 10: a motor vehicle having a drive train including a pulley decoupler.

Detailed Description

Fig. 1 and 2 each show, in a schematic representation, an exemplary embodiment of a torsional vibration damper 5, which is shown as identical as possible for the sake of clarity and to which cross reference is made to the description of identical components in the respective figures. The annular disk forms the output side 7. In the center of the common axis of rotation 2, the other disk element is configured, for example, as an input side 6. Alternatively, the annular disc is the input side 6 and the disc elements are the output side 7. In the following, the aforementioned variants are explained, wherein these terms are interchangeable.

As illustrated by the arrows, the drag torque 45 can be transmitted from the input side 6 to the output side 7, while the push torque 46 can be transmitted from the output side 7 to the input side 6. In one embodiment, the torque direction is reversed.

Three

intermediate elements

8, 9, 10 are arranged in an intermediate connection between the input side 6 and the output side 7, wherein the respective

intermediate element

8, 9, 10 is connected in a force-transmitting manner to the respective adjacent

intermediate element

8, 9, 10 by

energy storage elements

17, 18, 19 arranged in pairs. The respective

intermediate element

8, 9, 10 is supported on the input side 6 by means of a first rolling element 11, and the respective

intermediate element

8, 9, 10 is supported on the output side 7 by means of a second rolling element 12. The first rolling bodies 11 are supported in a rollable manner on the first transmission track 13 on the intermediate element side, and the complementary first counter track 15 is supported in a force-transmitting manner and thus in a torque-transmitting manner on the output side 6. The second rolling bodies 12 are supported in a rollable manner on the second transmission track 14 on the intermediate element side, and the complementary second counter track 16 is supported in a force-transmitting manner and thus in a torque-transmitting manner on the output side 7. The rolling

bodies

11, 12 are prestressed against the drive tracks 13, 14 and against the counter tracks 15, 16 by means of

energy storage elements

17, 18, 19 and are therefore guided on these tracks in a rollable manner. In the position shown, the

energy storage elements

17, 18, 19 hold the

intermediate elements

8, 9, 10 in the rest position against one another. In the first and second rolling

bodies

11, 12 at the third intermediate element 10 (according to the reference in the first intermediate element 8), a traction torque pair 23 is shown (for the sake of clarity, indicated in full with a partial representation) in the rest position, which is formed by the respective complementary ramp portions of the drive tracks 13, 14 and of the counter tracks 15, 16, and a thrust torque pair 25 is shown on the respective other side, which is formed by the complementary ramp portions of the drive tracks 13, 14 and of the counter tracks 15, 16. Likewise, for the sake of clarity only, the traction torque pairs 23 only on the first rolling elements 11 and correspondingly the thrust torque pairs 25 only on the second rolling elements 12 are shown in their entirety with a partial representation. However, these torque pairs are formed on each of the rolling

elements

11, 12 by the intermediate-element-side transmission tracks 13, 14 and the

complementary counter-tracks

15, 16, respectively. The operation of these tracks is explained in detail below. In the embodiment shown, the

intermediate elements

8, 9, 10 are supported on the input side 6 and the output side 7 only by the respective rolling

bodies

11, 12, and the

intermediate elements

8, 9, 10 are supported relative to one another by means of

energy storage elements

17, 18, 19. Preferably no additional guidance is provided.

In fig. 1, the first rolling elements 11 and the second rolling elements 12 of the respective

intermediate element

8, 9, 10 are arranged radially spaced apart from one another and lie on a common radius in the rest position. Thus, the first and second rolling elements have no spacing in the circumferential direction 22 in the rest position.

Fig. 2 shows an alternative embodiment of the arrangement of the two rolling

bodies

11, 12 of the respective

intermediate element

8, 9, 10 relative to one another, wherein the two rolling

bodies

11, 12 do not have a radial spacing but are spaced apart from one another in the circumferential direction 22. In the embodiment shown, the

energy storage elements

17, 18, 19 are of the same type and are arranged identically for better comparability.

Fig. 3 shows a schematic illustration of the moment balance according to the embodiment in fig. 1, and fig. 4 shows a force polygon of the first intermediate element 8, the second intermediate element 9 or the third intermediate element 10 with the first rolling element 11 and the second rolling element 12. The

intermediate elements

8, 9, 10 are guided out of their rest position and are inclined by an offset angle relative to the rest position and offset to the rest line 47. The stationary line 47 always extends through the moment compensation point 48 of the

intermediate element

8, 9, 10, but only in the rest position through the rolling axes of the two rolling

bodies

11, 12, but always through one of the two rolling axes (here the rolling axis of the second rolling body 12). If it is required that no additional (positive) guidance is provided for the

intermediate elements

8, 9, 10, a moment equilibrium must be present at this moment equilibrium point 48 of the

intermediate elements

8, 9, 10. The resultant force directions 28, 30 via the rolling

bodies

11, 12, i.e. the first pressure line 49 of the first rolling body 11 and the second pressure line 50 of the second rolling body 12, must always be oriented perpendicularly to the applied (theoretically infinitesimal) section of the drive tracks 13, 14 and extend through the moment compensation point 48. In order to always maintain compliance with this rule, a parallel line of a first line of action 51 of the first force 27 proceeding from the first energy storage element 17 and a second line of action 52 of the second force 29 proceeding from the further (for example, third) energy storage element 19, which are equally or proportionally spaced apart, intersect the two

pressure lines

49, 50 at the moment equilibrium point 48, so that no (effective) lever arm is produced. For a suitable pressing of the rolling

bodies

11, 12, the first force 27 and the second force 29 (here only shown at the second force 29) are divided into a tangential vector component 20 (functionally effective part) and a radial vector component 21 (pressed part of the rolling bodies 11). The orientation of the tangential vector component 20 results from a tangent to the force application point of the

intermediate element

8, 9, 10 in the circumferential direction 22 on a radius of the circle 53 on which the force application point lies. Further, as shown in fig. 4, the first force 27, the second force 29 and the resultant forces 54, 55 are required to form a self-cancelling force polygon. For this purpose, the first force direction 28, the second force direction 30 and the resultant force directions 56, 57 of the two rolling

elements

11, 12 must be present as shown. As a result of the position shown, both the first energy storage element 17 (see fig. 1) and the second energy storage element 18 (see fig. 1) are tensioned more strongly, so that an increased prestress acts on the

intermediate elements

8, 9, 10. The greater tensioning in this embodiment is due to the radially inward movement of the

intermediate elements

8, 9, 10, so that the

energy storage elements

17, 18, 19 are compressed with a radially inward movement and in the manner of a screw clamp between the adjacent

intermediate elements

8, 9, 10. The

intermediate elements

8, 9, 10 are therefore moved such that the spacing between the

intermediate elements

8, 9, 10 along the spring axes 31, 32, 33 of the

energy storage elements

17, 18, 19 is shortened relative to the rest position if increased stiffness is desired at higher torques (see fig. 5 to 8). Therefore, in order to correctly orient the pressure lines 49, 50, i.e. the lines of action of the resultant forces 54, 55 on the rolling

bodies

11, 12, it is necessary that the pressure lines 49, 50 always run perpendicular to the drive tracks 13, 14, in this case perpendicular to the first drive track 24 corresponding to the drag torque 45, which pressure lines intersect the respective rolling axes of the corresponding rolling

bodies

11, 12 and the torque balance point 48. The respective magnitudes of the resultant forces 54, 55 and the resultant force directions 56, 57 are derived inherently from the applied first force 27 and second force 29.

Fig. 5 to 8 show a torque-torsion angle diagram, wherein the torque axis 58 forms the ordinate and the torsion angle axis 59 forms the abscissa. In this embodiment, a traction torque curve with a positive torque and a torsion angle is shown on the right side of the ordinate, and a pushing torque curve with a negative torque and a torsion angle is shown on the left side of the ordinate.

In fig. 5, a first transmission curve 24 corresponding to the drag torque pair 23 and a second transmission curve 26 corresponding to the push torque pair 25 are shown in two-step progression, so that a flat curve progression exists when the torque magnitude is small and a steep curve progression exists when the torque magnitude is large.

Fig. 6 accordingly shows a two-step reduction variant, in which a steep curve rise is present when the torque magnitude is small, and a flat curve rise is present when the torque magnitude is large.

Fig. 7 shows a variant in which increasing and decreasing curves alternate, and in fig. 8 a comparison is shown of a rigid system with a steep curve trend shown in solid lines compared to a system with a flat curve trend shown in dashed lines.

For the embodiment of fig. 1 and 2 without additional guidance of the

intermediate elements

8, 9, 10, such transmission curves 24, 26 comply with the conditions of moment and force balance as illustrated in fig. 3 and 4. The illustrated drive curves 24, 26 are therefore implemented in superposition with the requirements for the drive tracks 13, 14 according to the description of fig. 1 (and fig. 2). Furthermore, in one embodiment, in the rest position, the force 25 or stiffness of the first energy storage element 17 is different from the second energy storage element 18 and is not implemented symmetrically as illustrated in fig. 1 and 2. This is also noted for the superposition to achieve the desired transmission curves 24, 26.

With the torsional vibration damper 5 proposed here, a cost-effective and effective influencing of the natural frequency can be achieved with a small number of components.

Fig. 9 shows a belt pulley decoupler 1 with a torsional vibration damper 5, for example, according to fig. 1, in a simplified section through, for example, a first intermediate element 8 (with continued reference to fig. 1 and the corresponding description). The input side 6 is here (optionally) formed in one piece with a shaft connection 60, which is here (optionally) shown connected to the drive shaft 36, for example a crankshaft, by means of a shaft connection 61. The output side 7 is formed here (optionally) in one piece with a belt pulley 35, 38, which forms a corresponding belt receptacle for a belt 41, which is here (optionally) embodied as a V-belt, radially on the outside. The drag torque 45 about the common axis of rotation 2, which is shown here as the output torque of the drive shaft 36, is conducted from the shaft connection 60 into the belt pulleys 35, 38 only by means of the torsional vibration damper 5.

The drag torque 45 is thus transmitted from the input side 6 to the first rolling elements 11, so that they roll on the input side 6, in this case on the first counter track 15 arranged radially outside the input side 6. This rolling movement is in turn transmitted to the intermediate element 8, here to a (complementary) first transmission track 13 arranged radially inside the intermediate element 8. The stepped embodiment of the first rolling elements 12 (and of the second rolling elements 12) is optional, but is advantageous for this sufficient axial position fixing of the respective rolling

elements

11, 12. The drag torque 45 is transmitted from the intermediate element 8 to the output side 7 by means of the second rolling elements 12. Instead, there, the movement of the intermediate element 8 forces the second rolling elements 12 to roll on the second drive track 14, which in turn requires the second rolling elements 12 to roll on a (complementary) second counter track 16 on the output side 7. The second drive track 14 of the intermediate element 8 is arranged here (optionally) radially on the inside, while the second counter track 16 of the output side 7 is arranged (correspondingly optionally) radially on the outside. For a better understanding of fig. 9 only, it should be pointed out that the (rectangular in the illustration) sections of the

respective parts

8, 35, 60 are radially aligned with the

raceways

13, 14 of the rolling

bodies

11, 12; 15. 16 are opposed to each other. When the pushing torque 46 is transmitted from the belt 41 to the drive shaft 36, the rolling

bodies

11, 12 are forced to move in opposite directions by means of the

tracks

13, 14, 15, 16. However, the rolling of the rolling

bodies

11, 12 on the

tracks

13, 14, 15, 16 is suppressed by the forces 27, 29 of the energy storage element 18 (here the second energy storage element 18: the first energy storage element 17 in active engagement is not shown, while the third energy storage element 19 shown is not in direct active engagement with the first intermediate element 8 shown). The energy storage element 18 is here (optionally) embodied as a helical compression spring. Thus, although a large torque forces only a relatively small torsion angle between the input side 6 and the output side 7 due to the high (spring) stiffness of the

energy storage elements

17, 18, 19, the oscillating movement of the rolling

bodies

11, 12 is only opposed by the deceleration rolling gear formed by the

tracks

13, 14, 15, 16 to a small (spring) stiffness. Thus, a large torque can be transmitted by using

energy storage elements

17, 18, 19 with a high (spring) stiffness. At the same time, a desired reduction of the (system) resonance frequency can be achieved due to the flexibility (low stiffness) of the movement of the rolling

elements

11, 12.

Fig. 10 schematically shows a motor vehicle 42 in a plan view. Vehicle 42 has a left drive wheel 43 and a right drive wheel 44, which are provided for propelling vehicle 42 in a main direction of travel (to the left according to the illustration along longitudinal axis 63). The torque required for this purpose is made available on demand by a drive machine 37, here (optionally) the internal combustion engine 4, by means of a drive shaft 36 of the drive train 34 shown. Furthermore, power is to be supplied to consumers, for example, a battery or an air conditioning compressor, by means of the drive machine 37. For this purpose, a belt drive 3 is provided, which connects the drive shaft 36 to a rotor shaft 39 of an auxiliary device 40 (e.g., a motor generator) in a torque-transmitting manner. The belt drive 3 comprises a first belt pulley 35 on a drive shaft 36 and a second belt pulley 38 on a rotor shaft 39, which are connected to one another by means of a belt 41 in a torque-transmitting manner. Here, (optionally) only the first pulley 35 comprises the pulley decoupler 1.

With the belt pulley decoupler proposed herein, the rotational speed fluctuations of the disturbances and the movement and noise of the belt can be reduced and the service life of the belt drive assembly can be extended.

List of reference numerals

1 Belt pulley decoupler

2 axis of rotation

3 Belt transmission mechanism

4 internal combustion engine

5 torsional vibration damper

6 input side

7 output side

8 first intermediate element

9 second intermediate element

10 third intermediate element

11 first rolling element

12 second rolling element

13 first drive track

14 second transmission rail

15 first corresponding track

16 second corresponding track

17 first energy storage element

18 second energy storage element

19 third energy storage element

20 tangential vector component

21 radial vector component

22 circumferential direction

23 drag torque pair

24 first transmission curve

25 push torque pair

26 second Transmission Curve

27 first force

28 first force direction

29 second force

30 second direction of force

31 first spring axis

32 second spring axis

33 third spring axis

34 drive train

35 first belt pulley

36 drive shaft

37 drive machine

38 second belt reel

39 rotor shaft

40 auxiliary device

41 leather belt

42 motor vehicle

43 left driving wheel

44 right driving wheel

45 drag torque

46 push torque

47 static line

48 moment balance point

49 first pressure line

50 second pressure line

51 first line of action

52 first line of action

Circle of 53 force action points

54 first resultant force

55 second resultant force

56 first resultant force direction

57 second resultant force direction

58 moment axis

59 axis of torsion angle

60 shaft connecting part

61 axle fastening part

62 longitudinal axis.

Claims

1. Belt pulley decoupler (1) with a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), wherein the belt pulley decoupler (1) comprises a torsional vibration damper (5) with at least the following components:

-an input side (6) for receiving torque;

-an output side (7) for outputting a torque;

-at least one intermediate element (8, 9, 10) in a torque-transmitting connection between the input side (6) and the output side (7);

-a first rolling element (11) and a second rolling element (12) of each intermediate element (8, 9, 10),

wherein the at least one intermediate element (8, 9, 10) has a first drive track (13) for the rolling of the first rolling bodies (11) and a second drive track (14) for the rolling of the second rolling bodies (12), wherein the input side (6) has a first counter track (15) which is complementary to the first drive track (13) and the output side (7) has a second counter track (16) which is complementary to the second drive track (14), wherein the first rolling bodies (11) are guided rollably between the first drive track (13) and the first counter track (15) and the second rolling bodies (12) are guided rollably between the second drive track (14) and the second counter track (16); and

at least one energy storage element (17, 18, 19) by means of which the intermediate element (8, 9, 10) corresponding to the energy storage element (17, 18, 19) is supported in a vibratable manner,

it is characterized in that the preparation method is characterized in that,

the energy storage elements (17, 18, 19) are arranged with a vector component (20) acting on the corresponding intermediate element (8, 9, 10) in a circumferential direction (22).

2. Belt pulley decoupler (1) with a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), wherein the belt pulley decoupler (1) comprises a torsional vibration damper (5) with at least the following components:

-an input side (6) for receiving torque;

-an output side (7) for outputting a torque;

-at least two intermediate elements (8, 9, 10) in a torque-transmitting connection between the input side (6) and the output side (7);

wherein the intermediate elements (8, 9, 10) each have a first drive track (13) for the rolling of the first rolling bodies (11) and a second drive track (14) for the rolling of the second rolling bodies (12), wherein the input side (6) has a first counter track (15) which is complementary to the first drive track (13) and the output side (7) has a second counter track (16) which is complementary to the second drive track (14), wherein the first rolling bodies (11) are guided rollably between the first drive track (13) and the first counter track (15) and the second rolling bodies (12) are guided rollably between the second drive track (14) and the second counter track (16); and

a number of energy storage elements (17, 18, 19) corresponding to the number of intermediate elements (8, 9, 10), by means of which the respective intermediate element (8, 9, 10) corresponding to the energy storage element (17, 18, 19) is supported in a vibratable manner,

wherein each of the intermediate elements (8, 9, 10) is supported on the respective at least one adjacent intermediate element (8, 9, 10) by means of the corresponding energy storage element (17, 18, 19),

it is characterized in that the preparation method is characterized in that,

only the first rolling elements (11) and the second rolling elements (12) are provided as rollable bodies for each intermediate element (8, 9, 10).

3. The pulley decoupler (1) according to claim 1 or 2, wherein exactly three intermediate elements (8, 9, 10) and exactly three energy storage elements (17, 18, 19) are provided, wherein a first intermediate element (8) and a second intermediate element (9) are mutually supported by means of the first energy storage element (17), the second intermediate element (9) and a third intermediate element (10) are mutually supported by means of the second energy storage element (18), and the first intermediate element (8) and the third intermediate element (10) are mutually supported by means of the third energy storage element (19).

4. The pulley decoupler (1) according to any one of the preceding claims, wherein the at least one intermediate element (8, 9, 10) is supported solely by means of the at least one corresponding energy storage element (17, 18, 19) and by means of the rolling bodies (11, 12).

5. The pulley decoupler (1) according to any one of the preceding claims, wherein the two rolling bodies (11, 12) are arranged radially spaced apart from one another and/or in the circumferential direction (22) spaced apart from one another.

6. The pulley decoupler (1) according to any one of the preceding claims, wherein the transmission tracks (13, 14) and the respective complementary corresponding tracks (15, 16) each comprise a traction torque pair (23) having a first transmission curve (24) and a push torque pair (25) having a second transmission curve (26), wherein the traction torque pair (23) is provided for transmitting torque from the input side (6) to the output side (7), wherein the push torque pair (25) is provided for transmitting torque from the output side (7) to the input side (6),

wherein the first transmission curve (24) and the second transmission curve (26) have at least in some regions mutually different transmission profiles.

7. Belt pulley decoupler (1) according to any one of the preceding claims, wherein the at least one intermediate element (8, 9, 10) is pre-tensioned by means of two counteracting energy storage elements (17, 18),

wherein preferably the first energy storage element (17) exerts a first force (27) and a first force direction (28) on the corresponding intermediate element (8, 9) and the second energy storage element (18) exerts a second force (29) and a second force direction (30) on the corresponding intermediate element (8, 10),

wherein the first force (27) and the second force (29) differ from each other in a rest position and/or the first force direction (28) and the second force direction (30) differ from each other in a rest position.

8. The pulley decoupler (1) according to any one of the preceding claims, wherein the at least one energy storage element (17, 18, 19) is a helical compression spring having a straight spring axis (31, 32, 33).

9. A belt drive (3) for a drive train (34), having at least the following components:

-a first belt pulley (35) for connection with a drive shaft (36) of a drive machine (37);

-a second belt pulley (38) for connection with a rotor shaft (39) of an auxiliary device (40); and

a belt (41) connecting the first belt pulley (35) and the second belt pulley (38) in a torque-transmitting manner,

wherein the first pulley (35) and/or the second pulley (38) comprise a pulley decoupler (1) according to any one of the preceding claims.

10. Drive train (34) having at least the following components:

-a drive machine (37) having a drive shaft (36);

-an auxiliary device (40) with a rotor shaft (39); and

-a belt drive (3) according to claim 9, by means of which the drive machine (36) and the auxiliary device (40) are connected to each other in a torque-transmitting manner.